Light-emitting diode (LED)
..................................................................................................................................
A light-emitting diode (LED) is a semiconductor device that emits incoherent narrow-spectrum light when electrically biased in the forward direction of the p-n junction. This effect is a form of electroluminescence.
An LED is usually a small area source, often with extra optics added to the chip to shape its radiation pattern [10]. The color of the emitted light depends on the composition and condition of the semiconducting material used, and can be infrared, visible, or near-ultraviolet.
